X-ray diffraction analysis of the crystal structures of different graphites

Graphites of different nature-pyrolytic, synthetic, thermally expanded, and natural graphites-were compared using X-ray diffraction analysis based on the (00l) reflection from the main crystal face. It was found that the (002) and (004) reflections are the superpositions of two components, which correspond to the structural phases of graphite with different interplanar spacing. The ratio between the integrated intensities of separated reflection components accounts for the ratio between these phases; along with interplanar spacing, this ratio characterizes graphites and makes it possible to detect difference between them. The long-range orders of reflection from the reference plane are responsible for more precise data on interplanar spacing; therefore, it is proposed to use the (004) reflection for characterizing graphites. A correspondence between the structure peculiarities of graphites determined by this method and the discharge capacity of lithium ion batteries with anodes made from these graphites was demonstrated.